tan2a = 2(tan a)/(1-(tan a)^2)具体怎么算?
tan(a+b)=2/5,tan(a-b)=1/4,求tana,tanb,tan2a
tan2A-tanA/tan2A+cotA=tan^2A 请问如何证明,
已知tan(a-b)=1/3,tan(a+b)=1/2,求tan2a,tan2b的值
tan2A = 2tanA/(1-tan^2 A) 中‘^’啥意思
证明tan(π/4+a)-cot(π/4+a)=2tan2a
证明:(1+tan a+cot a)/(1+tan^2 a+tan a)-cot a/(1+ tan^2 a)=sin
已知tan(a+b)=3,tan(a-b)=5 试求:tan2a和tan2 b的值
tan(a+b)=3 tan(a-b)=5 求tan2a tan2b的值
tan(a+b)=3,tan(a-b)=5,求tan2a和tan2b的值
已知tan(a+b)=3,tan(a-b)=5,求tan2a,tan2b的值~
tan(a+b)=5,tan(a-b)=3求tan2a,tan2b的值?
证明,tan(A/2)-1/tan(A/2)=-2/tana